iPhone 15 Plus battery health dropped from 99% to 95% in 10 days

Based on everything you've shown, it is well within normal. WhatsApp is eating up your battery faster than I'd be willing to let it do on my iPhone. I'd turn off notifications for that app completely and just check it once in a while.

As we've all suggested, you simply stop battery health decline and your battery is doing fine at this point. Worrying about it, won't help you as you cannot stop the natural decline of batteries. When the day comes that the health dips to 80%, it will then be time to pay Apple to replace the battery. Until then, stop worrying about something you cannot stop.

Well, it's not hard to see that WhatsApp is continuing to drain batteries probably faster than any other app on the planet.

In general over time, the Maximum Capacity of the battery will decline at about 1% for every 50 Charge Cycles. So, 212 Cycles divided by 50 = 4.24% or a current Maximum Capacity of about 94-95%. In a perfect world, at 250 Charge Cycles, the Battery Health would be about 95%.

I see nothing really unusual about your battery, and it is folly to try to predict future performance. In addition to WhatsApp, 5K cellular.....if you are using it.....can be real power drain as well as a fair cellular signal, since the phone spends too much time searching for a stronger signal.

I don't use WhatsApp. My iPhone 15 is just a bit above 250 Charge Cycles and the Max Capacity is at 96%....a bit better than average....but that can change of course.

You can make an appointment to take the phone in to an Apple Store to have the battery tested.......(Apple might be able to test the battery remotely)........but I think the techs will say that there is nothing really unusual about your battery and no cause for concern.

Apple won't replace a battery at no charge unless the Maximum Capacity falls to less than 80% in the first year. Every user seems to want their battery to perform better than average, but unfortunately averages are averages and they have a way of averaging out over time.

How long have you owned the phone? Battery health decline is NOT linear, meaning it can remain steady for a while, then drop a few points all at once. Generally, battery health declines on average 1% per month or for up to every 50 Charge Cycles. One thing you can't do is stop the natural decline of batteries, which with every full cycle charge will lose some health. So, please answer the following:

1. How long have you owned your iPhone?
2. In Settings > Battery > Battery Health, how many charge cycles does it show?

It's not all the unusual to see a 3-4% drop over a short period to be followed by a period where the battery does not decline at all for a month or two. Batteries are chemical devices and they do vary.

How old is the phone, month wise?

How many Charge Cycles has the battery completed?

Can you post a screenshot of what apps are using up the most power?

For what it's worth. I get better battery performance by ignoring Charge Limit settings and leaving the battery set for Optimized Battery Charging.

If the battery keeps declining, you will be at 80% before the battery is a year old, so you get a free replacement battery from Apple.